Absent or Delayed Periods: Causes and Treatment of Amenorrhea

Amenorrhea, the absence of menstrual periods, can be primary (never have had a period) or secondary (absence of periods for more than three months in someone who has previously had periods).

Primary amenorrhea can be diagnosed by absence of menstrual periods in girls age 15 years or older who have normal growth and pubertal development. It can also be diagnosed in cases of delayed puberty if girls have had no development of secondary sexual characteristics (such as breast development) by age 13 years.

Normal menstrual cycles

To have normal menstrual cycles, all of the following must be true:

• Cyclical fluctuations in hormonal production by the hypothalamus and pituitary (in the brain) and ovaries.
• Uterus builds up and sheds the uterine lining in response to hormonal stimulation.
• Vagina allows for outflow of menstrual blood.

Causes of absent or delayed periods

There are several causes of primary amenorrhea which can be categorized by anatomic, genetic, or hormonal conditions. 

Hormonal causes:

• Polycystic ovarian syndrome (PCOS)
• Slowed growth and delayed puberty
• Relative energy deficiency in sport (RED-S)
• Eating disorder or chronic malnutrition
• Hypopituitarism, GnRH deficiency, brain tumors

Ovarian causes:

• Premature ovarian insufficiency
• Abnormal development of the ovaries (gonadal dysgenesis)
• Turner syndrome, a genetic disorder caused by the absence or partial deletion of one X chromosome

Anatomic causes:

• Absent or underdeveloped uterus, cervix, or vagina (Müllerian agenesis)
• Transverse vaginal septum, a wall of tissue that forms in the embryonic stage and creates a blockage of the vagina
• Partial vaginal agenesis, a condition in which the vagina doesn’t develop
• Imperforate (blocked opening) hymen

Evaluation of absent or delayed periods

The evaluation of absent or delayed periods can vary depending on the child’s age and other factors. Sometimes, a physical exam which may involve a breast and/or external pelvic exam can be helpful, but this always depends on the child’s comfort level and does not necessarily need to be performed at the first visit. Blood tests, such as hormone levels or chromosome testing, may also be a part of the evaluation. A pelvic ultrasound (usually performed on the belly) is helpful in some cases to check for structural conditions that can cause an absence of periods. 

If a child has not had a period and has significant or cyclical abdominal pain, this may be a reason for a more urgent evaluation with ultrasound to look for structural conditions.

Treatment of absent or delayed periods

The treatment options vary depending on the reason for the delayed or absent periods. In cases where energy deficiency, eating disorder, or other health conditions are the cause of delayed or absent periods, treatment of these conditions can resolve the issue. For hormonal or ovarian causes, treatment may involve hormonal medications. For anatomic causes, sometimes surgery may be needed. In most cases, treatments are relatively straightforward and children live normal, healthy lives.